Calutrons



Sept. 16, 1958 w. M. PIERSON CALUTRONS Filed Oct. 15, 1945 INVENTOR. l/l/i/h'arw M pie/29w? ATTORNEY.

CALUTRONS William Pierson, Berkeley, Calif., assignor to the United States of America as represented by the United States Atomic Energy Commission Application October 15, 1945, Serial No. 622,466

7 Claims. (Cl. 250-419 The present invention relates to the apparatus for treating a polyisotopic substance to produce a plurality of segregable masses wherein the distribution of the constituent isotopes .has been altered so that one of the masses produced is enriched with respect to at least one isotope. The purpose of such treatment is to obtain a product characterized by an enhancement of the percentage of a selected isotope. More specifically, the invention relates to a device known in the art as a calutron, a term whose definition is any apparatus or machine where isotope separation or enrichment is achieved on a large scale yielding commercially useful quantities of one or more isotopes, by appropriate separative action on gaseous ions with electrostatic or electromagnetic means or combinations of them.

The foregoing definition has been taken from the Letters Patent of the United States No. 2,709,222 issued to Ernest 0. Lawrence on May 24, 1955. In that patent, the theory of isotopic separation and the principles of operation of a calutron are fully set forth, and will not here be repeated.

It may be stated generally, however, that the calutron to which this invention relates comprises essentially an evacuated tank disposed in a strong, substantially uniform magnetic field, and a transmitter and a receiver located within the tank.

The transmitter includes an ionizing arc chamber having an electron emitting. cathode associated therewith. The are chamber has an exit slit opening out into the tank, and spaced from the slit are two mutually spaced accelerating electrodes carried at a relatively high negative potential with respect to the arc chamber. As a result of this potential difierence, positive ions formed in the arc chamber are drawn out through the slit, and are projected in a slightly divergent beam into the tank.

A continuous supply of material, the isotopes of which are to be separated, is provided in the arc chamber. This may conveniently be accomplished by providing a charge reservoir in communication with the arc chamber, and the material or a suitable compound thereof may be provided in the charge reservoir.- The charge material may then be heated, and its vapor caused to flow at a controlled rate into the arc chamber, where ions of the several isotopes are formed and projected into the beam previously described.

Alternatively, of course, the charge material may be a compound which is a gas at normal conditions and is supplied directly to the arc chamber at a controlled rate.

The beam of positive ions of the polyisotopic substance is projected through the magnetic field in a direction normal to the field, and the beam is caused thereby to follow an arcuate path wherein the ions of the heavier isotope tend to concentrate in the region adjacent the outer periphery. From geometric considerations there results a substantial focusing of ions of the same isotope after approximately 180 of travel, and selective collection of isotopes may be made at this location.

The present invention relates more particularly to suitable means for mounting the evacuated vessel utilized in a calutron together with its associated ion generating and transmit-ting means and ion receiving means so that the entire unit may be conveniently positioned in the proper place between'the poles of the magnet and there readily adjusted in height. e

Accordingly, it is one object of this invention to provid means for mounting the evacuated vessel of a calutron for ready movement into and out of position between the pole faces of the magnet.

It is another object of this invention to provide means of the class described including convenient height adjusting means associated with supporting mechanism for the evacuated vessel.

It is a further object of this invention to-provide means for guiding the evacuated vessel of a calutron during its travel into or out of position between the pole faces of the magnet. Further objects and advantages appear here-v inafter.

In the accompanying drawing Figure l is a plan view, partly broken away and in part diagrammatic, illustrating a calutron embodying the features of the present invention;

Fig. 2 is a front elevation of the calutron shown in Fig. 1; and

Fig. 3 is a section taken on the line 3-3 of Fig. 1.

Referring more particularly to the drawings, there is shown a calutron indicated generally as 10 and including an upper pole face 11 and a lower pole face 12 of an electromagnet. It will be understood that suitable wind ings are associated with the poles of the electromagnet for establishing a strong magnetic field between the pole faces 11 and 12. An evacuated vessel or tank 13 is provided comprising a bottom wall 14 and a top wall 15, between which are mounted four upstanding corner stanchions 16. The side walls of the vessel 13 include suitable side frames 17. The rear. wall of the vessel includes a suitable rear frame 18 and the front wall of the vessel includes a suitable front frame 19. Each of the frames 17, 18 and 19 comprises a pair of vertical members 20 suitably secured as by continuous welds 20a to the corner stanchions 16 and a pair of horizontal frame members 21 suitably secured as by continuous welding to the bottom and top members 14 and 15, respectively.

Removably secured to the side frames 17 as by means of studs 25 are a pair of side plates 22. Similarly secured to therrear frame 18 is a rear plate 23. Likewise, similarly secured to the front frame 19 is a removable face plate 24.

Any of the plates 22, 23 or 24 may be provided with a port and means for connecting said port to a suitable evacuating system (not shown).

The removable face plate 24 may suitably support an ion generator 26 as by means of bushing 27. As will be understood by anyone skilled in the art, the ion generator 26 will include means for producing vapor of the substance to be ionized and means for ionizing the vapor. Associated with the ion generator 26 is'an ion' acceler ating member 28 by means of which ions' maybe drawn out of the ion generator 26 and projected as 'a beam transversely of the magnetic field existing between the pole faces 11 and 12. will-be caused, according to well; understood physical principles, to travel an arcuate path as indicated and in the event that the substance ionized includes elements or isotopes having a different charge to mass ratios the heavier of these elements will tend to concentrate along the outer side ofthe arcuate beam while the lighter of The face plate 24 likewise carries as by means of bush- PatentedSept, 16, 1958- The ion beam thus transmitted,

assaess ing 31 an ion receiver 36 so positioned as to receive and collect the ions transmitted in the ion beam. Suitable apertures and collecting pockets (not shown) may be provided in the receiver for the segregation of the elements being separated. A conduit 29 may be provided Within the bushing 27 for leading in the various elec-' trical apparatus necessary for supplying the ionizing potential, the vaporizing potential and the accelerating potential of the ion generator and accelerator.

It Will be noted that with the exception of the pole pieces 11 and 12 and their associated windings all of the essential operating elements of the calutron it) are contained within the tank 13 and are movable therewith. In order to position the tank 13 in its proper place between these spaced apart poie faces 11 and 12, there is on adjustable levers attached to the bottom of said tank,

provided tank supporting means and tank guiding means as more particularly described hereinafter. Secured to the bottom wall 14 of the tank 13 adjacent the corners thereof are shown four clevices 32 each including a plate 33 and depending leaves 34. The leaves 34 are apertured to receive a pin 35 held therein by a cotter key 36. Pivotally mounted on the pins 35 are four generally horizontally extending levers 37. Studs 38 are provided in threaded holes tapped vertically through the horizontally extending levers 37 which studs are adapted to engage on their upper ends the bottom wall 14'of the tank 13. The studs 33 may be adjusted to leave greater or lesser proportions thereof extending beyond the upper surface of the levers 37 and may be held in such adjusted position by means of lock nuts 39. Pins 41 are carried on the ends of the levers 37 to support rotatively the wheels 44 or the rollers 43. A pair of washers 43 is provided one on each side of each wheel 44 or roller 48 and the assembly is retained on the pins 41 by means of nuts .42. As indicated, the left-hand side of the tank 13 is thus provided with a pair of wheels 44 while the right-hand side of the tank 13 is provided with a pair of rollers 48. The Wheels 44 are each provided with a circumferential groove 45 adapted to engage an upstanding ridge 47 of a trackway 46. The smooth rollers 48 are adapted to engage a runway 49.

It will be noted that the tank 13 is thus mounted to be rolled into or out of position between the pole faces 11 and 12 and that by reason of the provision of the smooth rollers 48 along the righthand side engaging the runway 49 thermal expansion of the tank 13 or sidewise movements of the heavy structure during adjustment of the studs 38 will not cause a jamming ofthe wheels, yet the tank 13 is still positively guided in its travel by reason of the grooved wheel 44 engaging the track 46.

Furthermore, it will be noted that when the tank 13 has been rolled into position between the pole faces 11 and 12 it may be adjusted vertically with respect to the pole faces 11 and 12 simply by backing off the lock nut 39 and adjusting the stud 38 until the tank 13 has been placed at the height desired. At this point the lock nut 39 may be locked and the tank 13 will be securely held 7 in the desired position.

While there has been described what is at present considered to be the preferred embodiment of the invention, it will be understood that various modifications may be made therein and it is intended to cover in the appended claims all such modifications as fall within the true spirit and scope of the invention.

What is claimed is:

1. In a calutron, a magnet provided with apair of pole faces arranged in spaced-apart relation, a tank adapted to be adjustably positioned vertically between said pole faces, a plurality of grooved guide wheels mounted on adjustable levers attached to said tank, a plurality of plain rollers mounted on adjustable levers attached to said tank, means for adjusting'the position of each of said levers thereby to adjust said tank vertically with respect to said pole faces and to cause relative transverse movement of said rollers with respect to said wheels,

a plurality of plain rollers mounted on adjustable levers attached to the bottom of said tank, means including a guide track cooperating with said wheels and a runway cooperating with said rollers mounting said tank for movement along a predetermined path into and out of position between said pole faces, and means disposed below the bottom of said tank for adjusting the position of each of said levers, thereby to adjust said tank vertically with respect to said pole faces and to cause relative transverse movement of said rollers with respect to said wheels.

3. In a calutron, a magnet structure having a pair of spaced-apart pole faces, means for establishing a substantially uniform magnetic field between said pole faces, a fluid-tight vessel adapted to be adjustably positioned vertically between said polefaces and containing an ion generator, means for transmitting a beam of ions transversely of said magnetic field and an ion receiver adapted to receive and collect ions from said beam whereby said ions are segregated in accordance with their relative masses, a plurality of grooved guide wheels mounted on adjustable levers attached to said tank, a plurality of plain rollers mounted on adjustable levers attached to said tank, means for adjusting the position of each of said levers thereby to adjust said tank vertically with respect to said pole faces and to cause relative transverse movement of said rollers with respect to said wheels, and means including a guide track cooperating with said Wheels and a runway cooperating with said rollers mounting said tank for movement along a predetermined path into and out of position between said pole faces.

4. In a calutron, magnet structure having a pair of spaced-apart pole faces, means for establishing a substantially uniform magnetic field between said pole faces, a fluid-tight vessel adapted to be adjustably positioned vertically between said pole faces and containing an ion generator, means for transmitting a beam of ions transversely of said magnetic field and an ion receiver adapted to receive and collect ions from said beam whereby said ions are segregated in accordance with their relative masses, a plurality of grooved guide wheels mounted on adjustable levers attached to the bottom of said tank, a plurality of plain rollers mounted on adjustable levers attached to the bottom of said tank, means including a guide track cooperating with said wheels and a runway cooperating with said rollers mounting said tank for movement along a predetermined path into and out of position between said pole faces, and means disposed below the bottom of said tank for adjusting the position of each of said levers, thereby to adjust said tank vertically with respect to said pole faces and to cause relative transverse movement of said rollers with respect to said wheels.

5. In a calutron, a magnet structure having a pair of spaced-apart pole faces, means for establishing a substantially uniform magnetic field between said pole faces, a fluid-tight vessel adapted to be adjustably positioned vertically between said pole faces and containing an ion generator, means for transmitting a beam of ions transversely of said magnetic field and anion receiver adapted to receive and collect ions from said beam whereby said ions are segregated in accordance with their relative masses, a plurality of levers pivotally mounted adjacent the sides of said vessel, a plurality of rollers carried on the free ends of said levers and means including track means engaging said rollers and mounting said vessel for movement along a predetermined path into and out of position between said pole faces, and adjustable pins carried by said levers and adapted to engage the bottom of said vessel and adjust the height of said vessel with respect to said rollers.

6. In combination, a magnet having a pair of poles provided with pole faces arranged in substantially parallel spaced-apart relation, a tank adapted to be selectively positioned between said pole faces with respect to the opposing surfaces thereof and with respect to the peripheries of said poles, means for moving said tank into selected position with respect to said pole peripheries, and a plurality of independently adjustable means attached to said tank and adapted to adjust said tank into selected position with respect to the surfaces of said pole faces.

7. In combination, a magnet having a pair of poles provided with pole faces arranged in substantially parallel spaced-apart relation, a substantially rectangular, flatshaped tank adapted to be selectively positioned between said pole faces with respect to.the opposing surfaces References Cited in the file of this patent UNITED STATES PATENTS Long July 31,1923

OTHER REFERENCES Lawrence: The Bell System Technical Journal, vol.

XIII, No. 1, January 1934, article entitled Contemporary Advances in Physics, pages 114, 115, and 116 only pertinent. 

